The Emperor's Trousers

History buff Alessandro Lugli read his first book on Napoleon Bonaparte at age 9—and has pondered ever since the mystery of how the self-proclaimed French emperor died. A surgical pathologist in Switzerland, Lugli finally got his answer from Napoleon’s trousers.

The Corsican-born despot died in exile at age 52 in 1821. But his autopsy was as thorough and detailed as any today. Conducted by his personal physician, it listed stomach cancer as the cause of death. However, in 1961 findings of unnaturally high levels of arsenic in Napoleon’s hair challenged the autopsy and sparked poisoning theories. These were bolstered by portraits of the former dictator as corpulent—a girth not expected in someone dying from a gastric tumor.

Later studies undercut poisoning theories by finding consistent levels of arsenic in Napoleon’s hair throughout his life. And memoirs of eyewitnesses stated the dictator was vomiting, losing blood, and uninterested in food near the end. As Lugli read and reread the autopsy, he became increasingly convinced of its accuracy—and then hit on how to confirm it. “It’s not weight at the time of death but weight loss before dying that matters,” he says.

Using the autopsy and other forensic reports, Lugli and his colleagues at University Hospital in Basel calculated Napoleon’s weight when he died. Then they measured waistbands of 12 pairs of his pants, including the last ones he wore. With that information, they correlated his waist size to his weight over many years.

The results, published in the journal Human Pathology, show that Napoleon gained weight while in exile. But they also confirm Lugli’s hunch: Napoleon drastically slimmed down during the last six months of his life, shedding almost five inches from his waist and about 20 to 30 pounds. “We cannot say that [the results] are proof of gastric cancer,” Lugli says. “But the weight fits very well with that diagnosis.”